ruby on rails - Serializing a custom attribute -

i using active model serializer gem application. have situation user can have avatar id of medium.

i have avatar info saved redis. show avatar @ in serialized json, this:

class userserializer < activemodel::serializer include avatar

attributes :id,            :name,            :email,            :role,            :avatar  def avatar     medium.find(self.current_avatar)[0] end  #has_one :avatar, serializer: avatarserializer  has_many :media, :comments  url :user 

end

i query redis know medium in database, , use result in :avatar key.

down in code there line commented out, way found on https://github.com/rails-api/active_model_serializers/ page using custom serializer inside of serializer.

so problem. right :avatar comes in database want serialized before serve json. how can in case?

you need serialize avatar class:

class avatar   def active_model_serializer     avatarserializer   end end 

then use way:

class userserializer < activemodel::serializer include avatar    attributes :id,              :name,              :email,              :role,              :avatar    def avatar     # strange query object      avatar = medium.find(object.current_avatar).first     avatar.active_model_serializer.new(avatar, {}).to_json   end    has_many :media, :comments    url :user end